1. Field of the Invention
The present invention relates to a compensation plate used in a film coating device.
2. Description of Related Art
Referring to FIG. 4, a film coating device 200 includes film coating sources 10, compensation plates 11, and an umbrella-like canopy 12. Rings of substrates 13 are formed on a surface of the umbrella-like canopy 12 facing the film coating sources 10. Each film coating source 10 includes a heater 101 and raw material 102. The raw material 102 is heated and evaporated by the heater 101. The evaporated raw material 102 then travels to the substrates 13 and forms films thereon. Since distances and angles between the substrates 13 and the raw material 102 are not uniform, thickness of film deposited on the different substrates 13 may not be uniform. Therefore, to ensure uniformity of thickness for the films deposited on the different substrates 13, the compensation plates 11 are used.
Typically, manufacture of the compensation plates 11, begins with simulation in a personal computer, after which the compensation plate 11 is physically manufactured according to the simulation, and is tested in the film coating device 200 to qualify the compensation plate 11. If the compensation plate 11 does not pass qualification, another compensation plate 11 is produced and tested, until the compensation plate 11 is made that qualifies. Therefore, efficiency of manufacturing the typical compensation plate 11 is low, and material is wasted, which results in high manufacturing cost.
What is need, therefore, is to provide a compensation plate used in a film coating device, in which the above problems are eliminated or at least alleviated